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5 votes
Y=3x+13
2x=y-9
Solve for x and y points using addition method

2 Answers

6 votes
y = 3x + 13
y = -2x + 9
2y = x + 22
2y = x + 22
2 2
y = 1/2x + 11
1/2x + 11 = 3x + 13
-1/2x -1/2x
11 = 2 1/2x + 13
-13 - 13
-2 = 2 1/2x
-2 = 2 1/2x
2 1/2 2 1/2
-0.8 = x
y = 3(-0.8) + 13
y = -0.24 + 13
y = 12.76
(x, y) = (-0.8, 12.76)


User Jon Vaughan
by
7.9k points
2 votes

y=3x+13 \\ 2x=y-9 \ \ \ |-y-2x \\ \\ y=3x+13 \\ \underline{-y=-2x-9} \ \ \ \hbox{add the sides} \\ y-y=3x-2x+13-9 \\ 0=x+4 \\ x=-4 \\ \\ y=3x+13=3 * (-4)+13=-12+13=1 \\ \\ \boxed{(x,y)=(-4,1)}
User Iravanchi
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7.6k points